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      <h2><a href="./">Go by Example 中文版</a>: 变量</h2>
      
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            <p>在 Go 中，<em>变量</em> 需要显式声明，并且在函数调用等情况下，
编译器会检查其类型的正确性。</p>

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            <a href="http://play.golang.org/p/ow-dxJqW0-0"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
          <div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
</pre></div>

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          <div class="highlight"><pre><span class="kn">import</span> <span class="s">&quot;fmt&quot;</span>
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          <div class="highlight"><pre><span class="kd">func</span> <span class="nx">main</span><span class="p">()</span> <span class="p">{</span>
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            <p><code>var</code> 声明 1 个或者多个变量。</p>

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          <div class="highlight"><pre>    <span class="kd">var</span> <span class="nx">a</span> <span class="p">=</span> <span class="s">&quot;initial&quot;</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nx">a</span><span class="p">)</span>
</pre></div>

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            <p>你可以一次性声明多个变量。</p>

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          <div class="highlight"><pre>    <span class="kd">var</span> <span class="nx">b</span><span class="p">,</span> <span class="nx">c</span> <span class="kt">int</span> <span class="p">=</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nx">b</span><span class="p">,</span> <span class="nx">c</span><span class="p">)</span>
</pre></div>

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            <p>Go 会自动推断已经有初始值的变量的类型。</p>

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          <div class="highlight"><pre>    <span class="kd">var</span> <span class="nx">d</span> <span class="p">=</span> <span class="kc">true</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nx">d</span><span class="p">)</span>
</pre></div>

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            <p>声明后却没有给出对应的初始值时，变量将会初始化为 <em>零值</em> 。
例如，<code>int</code> 的零值是 <code>0</code>。</p>

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          <div class="highlight"><pre>    <span class="kd">var</span> <span class="nx">e</span> <span class="kt">int</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nx">e</span><span class="p">)</span>
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            <p><code>:=</code> 语法是声明并初始化变量的简写，
例如 <code>var f string = &quot;short&quot;</code> 可以简写为右边这样。</p>

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          <div class="highlight"><pre>    <span class="nx">f</span> <span class="o">:=</span> <span class="s">&quot;short&quot;</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="nx">f</span><span class="p">)</span>
<span class="p">}</span>
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          <div class="highlight"><pre><span class="gp">$</span> go run variables.go
<span class="go">initial</span>
<span class="go">1 2</span>
<span class="go">true</span>
<span class="go">0</span>
<span class="go">short</span>
</pre></div>

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        下一个例子: <a href="constants">常量</a>
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